Float actuated gas vent



y 20, 1965 L. w. YOUNG ETAL 3,195,557

FLOAT AG'IUATED GAS VENT Filed April 25, 1963 ELECT. SUPPLY SOURCEINVENTORS Zawrewce W )wng' Passe V. Me/ocfie A T TORNE YS United StatesPatent Delaware Filed Apr. 25, 1963, Ser. No. 275,546 2 Claims. (Cl.137-202) This invention relates to separators and more particularly toan apparatus for separating two phases of a cryogenic medium (i.e.liquid and gas).

The use of cryogenic liquids in industrial applications has becomeincreasingly more prevalent. In this connection, cryogenic liquids arebeing employed in a number of diverse industrial applications, forexample, as a refrigerating means in deflashing and trimming apparatusfor molded parts. In such applications it is extremely important bothfrom the standpoint of economy and efliciency that the cryogenic mediumbe utilized in aliquid state. Inasmuch as some vaporization of thecryogenic liquid occurs during passage through the system supplying samenotwithstanding the type or degree of insulation employed therein, theneed exists for an effective apparatus which can be utilized to separatecryogenic vapor from the cryogenic liquid being supplied. To beeffective, such. a separator should provide a continuous supply ofcryogenic liquid at the point of utilization while at the same timesalvaging the cryogenic vapor for reliquification. Moreover, theseparating apparatus should be capable of effecting separation of thetwo phases of the cryogenic liquid rapidly and without causingadditional loss of cryogenic liquid as a result of the separationprocess.

Accordingly, it is the prime object of the present invention to providean improved apparatus for effecting the separation of two phases of acryogenic medium.

Still another object of the present invention resides in the provisionof a separation apparatus for a cryogenic medium which carries out theseparation of the vapor state from the liquid state in a rapid andefficient manner without causing additional loss of the cryogenicliquid.

A further object of the present invention is to provide a separationapparatus for a cryogenic medium which is relatively inexpensive both inconstruction and operation.

Other objects and advantages of the present invention will becomeapparent from the, following detailed description when considered inconjunction with the accompanying drawing wherein the single figure is asimplified elevational view of a preferred embodiment of the separationapparatus with portions of the apparatus confining enclosure brokenaway.

In general, a preferred embodiment of the separation apparatus of thepresent invention includes a suitably insulated separation chamberwhereto the cryogenic medium is supplied and wherein the cryogenicliquid is separated from the cryogenic vapor. A suitable float, which issupportable by the cryogenic liquid but not so by the cryogenic vapor,is positioned within the separation chamber. The float has a piston rodor shaft secured thereto which extends from the separation chamber to aregion which houses a responsive switch means. As the height of thefloat varies in response to variations in the level of the cryogenicliquid within the separation chamber, a switch actuating piston membersecured to the piston rod is advanced relative to the responsive switchmeans. When a substantial amount of cryogenic vapor accumulates in theseparation chamber as indicated by the position of the float, theresponsive switch means is actuated, thereby causing the opening of avent valve that is connected to a vapor outlet for the separationchamber.

When opened, the vent valve allows the cryogenic vapor to be dischargedfrom the chamber. Thereafter, as a suitable volume of cryogenic liquidis again accumulated within the chamber, the float is raised resultingin the closure of the vent valve. The Vent valve is sized so that arelatively rapid discharge of the accumulated vapor is achieved and acontinuous supply of pure cryogenic liquid is realized. Moreover, thevapor outlet is suitably shielded to preclude the discharge of cryogenicliquid therethrough as vapor is being vented from the chamber.

Referring specifically to the drawing, a preferred embodiment of a gasseparator in accordance with the present invention includes a separationchamber 11 that is defined by a cylindrical housing 12, which ispreferably formed of a material such as stainless steel. The cylindricalhousing 12 is confined within a rectangular enclosure 13 formed of amaterial such as aluminum. More particularly, the cylindrical housing,which defines the separation chamber 11 is positioned in spaced relationto the inner walls of the enclosure 13 and a suitable layer 15 ofthermal insulation is provided in the region therebetween. Preferably,this insulation is polyurethane which is foamed in the region betweenthe housing 11 and the enclosure 13 subsequent to the mounting of thehousing therein although other forms of insulation can also be employed.

The separation chamber defining housing 12 is provided with a liquidinlet port 14, a liquid outlet port 16 and a vapor outlet port 17. Eachof these ports communicate with suitable coupling members exteriorly ofthe enclosure 13 through conduit members 18 that maintain the housing 12in fixed relation within the enclosure. As shown, in the drawing, theliquid inlet port 14 is positioned in a plane above the liquid outletport 16 and the vapor outlet port 17 is located near the uppermostregion of the cylindrical housing.

In this connection, it is important that the liquid inlet port 14 bemaintained above the liquid outlet port 16 so that any vapor enteringthe chamber throu h the port 14 does not pass directly to the outletport. Moreover, it is important that the ports 14 and 17 be maintainedin suitable spaced relation so that incoming liquid is precluded frombeing discharged from the vapor outlet port. To further preclude thisdischarge of liquid, the vapor outlet port 17 is shielded by a bafliemember 19. In the illustrated embodiment of the invention, the bafiiemember 19 is a closed end cylinder provided with a plurality ofrelatively small vapor discharge apertures 1% along the upper surfacethereof and a single drain aperture 19b along the lower surface thereof,the function of which will be more fully hereinafter described.

A spherical float 21, which is preferably formed of stainless steel, isconfined within the separation chamber 11. The float 21 is selected sothat it is supported by cryogenic liquid which accumulates within thechamber .but not so by an accumulation of cryogenic vapor due to therelatively low density of the latter. A shaft or piston rod 22 issecured to the float 21 and extends vertically upwardly through asealing and bearing member 23 that is confined within a conduit member24. As shown, the lower end of the conduit member 24 is suitably securedto an apertured portion in the upper wall of the cylindrical housing 12and extends outwardly through the thermal insulation 15, an aperture inthe upper wall of the enclosure 13, and extends into a housing 26 for aselectively actuable switch 29.

More particularly, the conduit member 24 extends into and through thehousing 26 and serves as a guide for a switch actuating piston member 27that is secured to the upper extremity of the shaft or piston member 22.As shown, the piston member 27 is mounted within the conduit member 24for limited movement therein and relative to the selectively actuableswitch 29, which might be wardly and away from the switch in response tothe low.

ering of the level of cryogenic-liquid within the separation chamber 11,the switch 29 is actuated thereby.

.In this connection, the switch 29, which is preferablyadjustably-mounted on the conduit member 24, is. electrically connectedto a solenoid'30 by conductors 31.

As shown,the conductors 31 extend from the housing 26 and are connectedto'a suitable source 32 of electrical' lowering of the level of thecryogenic liquid, an energizing circuit for the solenoid is provided bythe closure of the switch 29 resulting from this movementof the pistonmember relative thereto.

The actuated element of the solenoid 30 is mechanically connectedto avalve 34 that controls the passage of vapor from the separation chamber11 through the vapor outlet 17 and the conduit 18 associated therewith.In this connection, the valve 34 is connected to the cone duit 18 sothat a critically. sized orifice provided by the valve is either fullyopen or'completely closed in response to the action of the solenoid 30.i

Themanner in which the effective separation of cryo genic liquid andvapor is effected by the aforedescribed embodiment'will best beunderstood from a consideration of a typical operational period. In thisconnection, when utilized in an industrial application requiring purecryogenic liquid, the separator is preferably. located at the highestpoint in the system employing same; The

liquid inlet port 14 is connected through the coupling member 20 to asuitably insulated inlet line that supplies cryogenic liquid from asuitable-storage'or containment vessel (not shown) through the separatorto the point of utilization. Inasmuch as some vaporization accompaniesthis transferrence' of the cryogenic liquid, both liquid and vapor areintroduced through the'inlet port 14;tothe chamber 11.

For purposes of the remaining portion of this description, it will beassumed that .a suitable amount of cryogenic liquid has accumulatedWithin the chamber 11 so that the float 21 is in the position shown inthe drawings. When the floati's so positioned, the vent valve 34 isclosed, and .a continuous supply of cryogenic liquid is dischargedthrough the liquid outlet port 16 and supplied to the apparatusassociated With'theseparator.

If, for example, aportion of the liquid being supplied vaporizes duringpassage'through the inlet line, the vapor. introduced to thecha'm-berrises to the liquid-vapor intere When the magnetic piston 27, which isconnected to the float by the piston rod 22, is ultimately advancedoutof proximity with the switch 29, the normally open contacts of theswitch are closed and energizing current is sup; plied to the solenoid30. 'When energized, the solenoid 3%) effects the opening'of the valve34. Upon, opening,

the valve provides a discharge path for the vapor ac cumulatingin theseparation chamber 11.

More particularly, when the valve 34, is open, vapor in the chamber. 11passes through the apertures in the shielding cylinder19, the vaporoutlet port 17, the conduit 78, the coupling member'ZO, and through thecriti- 4 e 'cally sized orifice provided by the valve 34 to a suitablecompressor-(not shown) associated with the separator.

In a conventional manner, the cryogenic vapor discharged from'thechamber is recompressed and returned to the 5 supply orcontainmentvcssel connected to the inlet line for the separator.

As the accumulated vapor is discharged, and cryogenic liquid againaccumulates within the chamber, the float 21 and the piston member 27remotely securedjthereto are advanced upwardly. That is, the disc'haigeof vapor from the chamber 11' and the pressurerelief" incident theretoallows liquid to flowinto the chamber at a faster rate than liquid isdischarged therefrom and the liquid level V is reestablished.v fTheresulting return movement of the 15 'magnetic'piston member 27 causesthe switch 29 to be actuated and again openthe energizing circuit forthe solenoid 30 When the solenoid 30 is deenergized, the valve 34 (i.e.the critically sized vent'orifice) is again fully closed. Thisaforedescribed intermittent venting of accumulated vapor continues as acontinuous supply of cryogenic liquid'is being supplied from the sourcethrough v,the separator to the point of utilization.'

In this connection, it is important that the accumulated cryogenic vaporbe vented-from the chamber at a suitaj ble' rate tov insure a continuoussupply of pure cryogenic liquid at the outlet port 16. However, thevapor should not be discharged so rapidly thatviolent splashing of theliquid within the chamber'results', since such splashing leads to' thedischarge of cryogenic liquid through the vapor outlet 17 and inhibitsthe efliciency, of the delivery and separation operations.

One example of separator operation clearly illustrates the results thatcan be achieved by employing theffeatures of the present invention flnthis instance, cryogenic liquid was continuously supplied'through theinlet port 14 at a pressure of 20 p.s.i .g., and satisfactory andefiicient separation'was effected" by an orifice in the valve 34 whichaccommodatedthe venting of accumulating'vapor delivery pressure oradjusting the length of' the float chamber to provide more vapor space.In such cases, "the orifice, size is adjusted to conform to thesevariations.

' To further insure that cryogenic liquid is not lost through the vaporoutlet port 17 during the venting process, 'the shielding, cylinder 19is employed. While the vapor discharge apertures 1% provided thereinreadily accommodate;thepassage of vapor from the chamber 11, this memberserves as a battle and effectively precludes liquid frombeing-discharged from the vaporoutlet port 17. However, shouldsomeliquid pass into the cylinder,

I the drain aperture 19b in the lower surface thereof accommodates thedischarge of this liquid back into the separation'chamber.

It should be vunderstood'thatthetoregoing is merely illustrative of theinvention, and various equivalent structures can be devised withoutdeparting from the invention as set' forth in the'accompanying claims.

What is claimed is: i a v 1. Apparatus for effecting the separation oftwo phases of a cryogenic medium being supplied from a source thereoftoa point of utilization; which apparatus comprises an insulated housingwhich idefinesa chamber for receiving'the cryogenic medium. positionedin elevated relation with respect to'both'said sourceand said point ofutilization; said housing including an inlet port where through themedium'is supplied to the chamber, a liquid outlet port positionedbelowthe inlet port, and a vapor 'outplet port positioned substantiallyabove said inlet port; selectively energiz able means connected to saidvapor outlet port'so as to' normally block the vapor discharge pathprovidedthereby; switch means mountedon said insulated housing andelectrically connected to said last mentioned means for controlling theenergization thereof; a float member-confined within said housing, saidfloat member at a rate of standard cubic feetper minute. Obvious:

13/, other venting rates can be obtained by varying the beingsupportable by cryogenic liquid but not supportable by cryogenic vapor;switch actuating means connected to said float member for movementtherewith and relative to said switch means; said switch actuating meanscausing the actuation of said switch means in direct response to thelowering of the level of the cryogenic liquid within said chamber andthe corresponding downward movement of said float member below apreselected level, said actuated switch means effecting the energizationof said blocking means and the opening of said vapor discharge path; anda chamber defining spill over shield secured to the housing insurrounding relation to said vapor outlet port to preclude the spillingover of cryogenic liquid through said port as vapor is discharged, saidshield having a series of orifices to accommodate the flow of vaportherethrough each of which orifice is of a cross sectional area which issubstantially smaller than the cross sectional area of said vapor outletport.

2. Apparatus for effecting the separation of two phases of a cryogenicmedium being supplied from a source thereof to a point of utilization;which apparatus comprises an insulated housing which defines a chamberfor receiving the cryogenic medium positioned in elevated relation withrespect to both said source and said point of utilization; said housingincluding an inlet port wherethrough the medium is supplied to thechamber, a liquid outlet port positioned below the inlet port, and avapor outlet port positioned substantially above said inlet port;selectively energizable means connected to said vapor outlet port anddefining at least a portion of the vapor discharge path from saidchamber, said last mentioned means including means normally blockingsaid vapor discharge path; switch means mounted on said insulatedhousing and electrically connected to said selectively energizable meansfor controlling the energization thereof and the opening of saiddischarge path; a float member confined within said housing, said floatmember being supportable by cryogenic liquid but not supportable bycryogenic vapor; switch actuating means connected to said float memberfor movement therewith and relative to said switch means, said switchactuating means causing the actuation of said switch means in directresponse to the lowering of the level of the cryogenic liquid Withinsaid chamber and the corresponding downward movement of said fioatmember below a preselected level, said actuated switch means effectingthe opening of said vapor discharge and maintaining said discharge pathin an open condition during the actuation thereof; and an elongatedtubular horizontally disposed spill over shield having one end closedand the other end secured in surrounding relation to said vapor outletport to preclude the spilling over of cryogenic liquid through said portas vapor is discharged, said shield having an inner diameter lsightlylarger than said vapor outlet port and being positioned so that thelowermost surface of the interior of said shield is in spaced relationto the bottom edge of said outlet port, said shield being provided withat least one orifice at the uppermost surface thereof to accommodate theflow of vapor therethrough, and further being provided with a drainorifice at the lowermost surface thereof so as to allow the draining ofsuch cryogenic liquid as may spill over into said shield to prevent saidliquid from entering said vapor outlet port.

References Cited by the Examiner UNITED STATES PATENTS 2,120,048 6/38Turner 137412 2,367,851 1/45 Eaton 137412 XR 2,500,320 3/50 Pefi 137202XR 2,848,879 8/58 Hesson 137202 XR WILLIAM F. ODEA, Primary Examiner.

ISADOR WEIL, Examiner.

1. APPARATUS FOR EFFECTING THE SEPARATION OF TWO PHASES OF A CRYOGENICMEDIUM BEING SUPPLIED FROM A SOURCE THEREOF TO A POINT OF UTILIZATION;WHICH APPARATUS COMPRISES AN INSULATED HOUSING WHICH DEFINES A CHAMBERFOR RECEIVING THE CRYOGENIC MEDIUM POSITIONED IN ELEVATED RELATION WITHRESPECT TO BOTH SAID SOURCE AND SAID POINT OF UTILIZATION; SAID HOUSINGINCLUDING AN INLET PORT WHERETHROUGH THE MEDIUM IS SUPPLIED TO THECHAMBER, A LIQUID OUTLET PORT POSITIONED BELOW THE INLET PORT, AND AVAPOR OUTLET PORT POSITIONED SUBSTANTIALLY ABOVE SAID INLET PORT;SELECTIVELY ENERGIZABLE MEANS CONNECTED TO SAID VAPOE OUTLET PORT SO ASTO NORMALLY BLOCK THE VAPOR DISCHARGE PATH PROVIDED THEREBY; SWITCHMEANS MOUNTED ON SAID INSULATED HOUSING AND ELECTRICALLY CONNECTED TOSAID LAST MENTIONED MEANS FOR CONTROLLING THE ENERGIZATION THEREOF; AFLOAT MEMBER CONFINED WITHIN SAID HOUSING, SAID FLOAT MEMBER BEINGSUPPORTABLE BY CRYOGENIC LIQUID BUT NOT SUPPORTABLE BY CRYOGENIC VAPOR;SWITCH ACTUATING MEANS CONNECTED TO SAID FLOAT MEMBER FOR MOVEMENTTHEREWITH AND RELATIVE TO SAID SWITCH MEANS; SAID SWITCH ACTUATING MEANSCAUSING THE ACTUATION OF SAID SWITCH MEANS IN DIRECT RESPONSE TO THELOWERING OF THE LEVEL OF THE CRYOGENIC LIQUID WITHIN SAID CHAMBER ANDTHE CORRESPONDING DOWNWARD MOVEMENT OF SAID FLOAT MEMBER BELOW APRESELECTED LEVEL, SAID ACTUATED SWITCH MEANS EFFECTING THE ENERGIZATIONOF SAID BLOCKING MEANS AND THE OPENING OF SAID VAPOR DISCHARGE PATH; ANDA CHAMBER DEFINING SPILL OVER SHIELD SECURED TO THE HOUSING INSURROUNDING RELATION TO SAID VAPOR OUTLET PORT TO PRECLUDE THE SPILLINGOVER OF CRYOGENIC LIQUID THROUGH SAID PORT AS VAPOR IS DISCHARGED, SAIDSHIELD HAVING A SERIES OF ORIFICES TO ACCOMMODATE THE FLOW OF VAPORTHERETHROUGH EACH OF WHICH ORIFICE IS OF A CROSS SECTIONAL AREA WHICH ISSUBSTANTIALLY SMALLER THAN THE CROSS SECTIONAL AREA OF SAID VAPOR OUTLETPORT.